1. Field of the Invention
The present invention is in the field of apparatus and methods used to clean foreign material, varnish, oxidation products, metallic wear particles, and other environmental and operating residues from an automotive automatic transmission. More particularly, the present invention relates to a machine for connection in a relation of fluid flow recirculation or exchange with an automotive automatic transmission, and which provides for circulation of a cleaning fluid through the transmission, as well as for replacement of the used transmission fluid from the transmission with new fluid which is provided from a reservoir associated with machine. The machine includes a set of especially configured hoses each of which are fitted at their opposite ends with quick-disconnect couplings. One of the quick-disconnect couplings is configured to interface with the fluid exchange machine, and the other is configured to interface with any one of a variety of adapter fittings which are provided in a set. The set of fittings includes pairs of complementary adapter fittings. The pairs of adapter fittings of the set each include differently configured and complementary end fittings which on the one hand connect with the quick-disconnect couplings on the hoses and on the other hand also connect with various ones of the wide variety of fittings and connections used in various automotive vehicles and the wide variety of automotive automatic transmissions of these vehicles.
2. Related Technology
A conventional cleaning machine for an automotive automatic transmission is known according to U.S. Pat. No. 5,337,708, issued Aug. 16, 1994 to We-Yu Chen. The '708 patent is believed to teach a transmission fluid change machine in which an external ATF circulation loop is opened, with part of the machine completing this loop in one mode of operation. The used transmission fluid, possibly with a transmission flushing solution, is circulated in the external circulation loop as completed by the machine. When operated in an exchange/refill mode, the machine receives old transmission fluid and supplies new fluid at a selected pressure or volume delivery rate. The machine is intended to be operated from the 12 volt power supply of the automobile or other automotive vehicle being serviced. The new transmission fluid tank of this device appears to be provided with a level sensor, so that the system can be reverted to loop configuration (filtration/flushing) should the level of new ATF drop too low. A pump is utilized to move new ATF from the fluid tank to the transmission being serviced. However, it is not clear from this patent that in the event the power supply to this device is interrupted or the pump ceases to operate, how the configuration of the device is reverted to loop form so that the transmission of the vehicle being serviced is not damaged by being operated with insufficient ATF. Although this patent asserts that a power failure will cause reversion of the apparatus to loop configuration in the event of a power failure, how this change in configuration is to be effected or powered is not set out.
Another conventional transmission fluid change apparatus is disclosed by U.S. Pat. No. 5,318,080, issued Jun. 7, 1994 to James P. Viken. The '080 patent is believed to disclose an apparatus in which supply of the new ATF is provided by a pressurized storage container, which is pressurized by the used ATF withdrawn from the transmission. The storage container has a chamber which is separated into two sub-chambers expanding and contracting in opposition by a flexible wall. As used ATF from the transmission is received into one sub-chamber, new ATF is displaced from the other sub-chamber to the transmission. This device has the limitation that the volume of new transmission fluid supplied to the transmission can not easily exceed the volume of old fluid removed from the transmission. This may be a disadvantage because flushing of contaminated old fluid from the transmission may require infusion of more than an equal volume of new transmission fluid.
Yet another conventional transmission service machine is known according to U.S. Pat. No. 5,370,160, issued Dec. 6, 1994 to Zachary T. Parker. The '160 patent is believed to disclose a service machine in which the external ATF fluid return loop for the transmission is completed by a reservoir from which the fluid is drawn by a pump. Accordingly, in the event that operation of the pump is interrupted while the serviced vehicle continues to operate, the transmission of the vehicle is at risk of damage from dry running. A separate pump is used to supply new ATF to the transmission, but this pump may suffer from the same power supply interruption, so that the transmission is still at risk of damage from dry running. The Parker '160 patent does not appear to provide a closed external ATF circulation loop for the transmission being serviced (other than the one relying on operation of a pump), and does not use a three-way valve to complete or open such an external ATF circulation loop.
Still another conventional apparatus for exchanging the fluid of an automatic transmission is known in accord with U.S. Pat. No. 5,447,184, issued Sep. 5, 1995 to Eduardo Betancourt. The '184 patent is believed to disclose an apparatus in which a reservoir for new ATF is provided so that the volume of new fluid supplied to the transmission can exceed the withdrawn volume. The '184 patent appears to include a sensor operating a bell to bring the attendant's attention to the fact that the supply of new ATF is at risk of running out. However, if the attendant is not close at hand or is inattentive, the transmission may still be damaged if the supply of new ATF runs out while the transmission is being flushed. Still further, the device taught by the '184 is not believed to provide any safeguard to protect the automatic transmission in the event of a power failure to the apparatus while the transmission is being flushed during operation.
Finally, another conventional automatic transmission flush apparatus is known according to U.S. Pat. No. 5,472,064, issued Dec. 5, 1995. The feature which the '064 patent appears to contribute to the art is the use of a conventional directional flow control valve. This flow control valve allows connection of the apparatus to the external ATF circulation loop (i.e., the ATF cooler loop) of the transmission with no need to take note of the direction of fluid circulation in this loop. If the internal fluid flow direction of the apparatus happens to be correct, there is no need to change the valve position. In the event the internal fluid flow direction of the apparatus is incorrect, then reversing the position of the flow control direction valve will match the internal flow direction to the direction of the fluid flow in the external ATF flow loop of the transmission.
A persistent problem and disadvantage with all of the conventional machines noted above for service of an automotive automatic transmission, as well as with other conventional machines for this purpose, is that the machines each require a great number of hoses, fittings, and adapters in order to interface in fluid recirculation and exchange relationship with the wide variety of different automotive automatic transmissions, and the vehicles in which these transmissions are installed. That is, automotive automatic transmissions generally have a transmission fluid cooler, which in some cases is configured as a liquid-to-air heat exchanger mounted near the vehicle's radiator, and in other cases is configured as a liquid-to-liquid heat exchanger (i.e., transferring heat from the transmission fluid to engine coolant, which is then cooled in the "radiator" (which itself is a liquid-to-air heat exchanger). In many cases, the fittings and adapters are configured as end termination structures which are permanently attached to lengths of hose, sometimes including sections of rigid metal tubing permanently attached to lengths of hose, and to which an end termination fitting or coupling is permanently secured.
Accordingly, a wide variety of differing sets of hoses, adapters, couplings, and fittings have been provided for use with these machines. Depending upon the variety of such fittings, couplings, and adapters, various ones of the conventional machines may or may not be able to service the automatic transmissions of particular automotive vehicles. That is, the proper set a couplings, adapters, and fittings may not be available for some vehicles. Further, the variety of hoses, adapters, couplings and fittings, has necessitated the provision of a considerable storage space for all this equipment. And service technicians must study instructions for all these couplings, fittings, hoses, and adapters, or simply figure out an arrangement on their own, in order to service the transmission of various vehicles. Dependent upon the ingenuity of particular service technicians, a convenient or more difficult interconnection with a particular vehicle may be accomplished.
In other words, conventionally, this large number of hoses, fittings, couplings and adapters that are encountered in servicing of automotive vehicles has been considered necessary in order to interface with the great variety of differing transmission installations and connections provided by the large number of differing vehicles encountered in a contemporary automotive service environment. A disadvantage of the large number of hoses in addition to the storage space required for these in a service area, is the necessity for a service technician to deal with a long and heavy piece of hose while making the interconnections of this hose to a vehicle being serviced. After the hose is interconnected with a vehicle to be serviced, then the hose is connected to a service machine, and the service procedure can begin. However, access in many modern cars and other vehicles to the transmission fluid cooler loop is not easy. Having to deal with this commonly restricted access and to also manipulate a cumbersome length of hose while making the connections is not an easy task.
Further, in addition to representing a considerable investment in hardware, some of which is only rarely used, this large number of hoses, fittings, and adapters disadvantageously requires a considerable storage space in, adjacent to, or accessible conveniently close to a transmission service machine. Also, because of the large number of hoses, adapters, and fittings, there also is presented the possibility that the service technician who uses the machine will use an incorrect fitting or adapter, possibly resulting in leakage of transmission fluid. Further, the great number of hoses, fittings, and adapters required by conventional transmission service machines provides an abundant opportunity for the service technician to lose or misplace a hose or fitting, so that some vehicles can not be serviced until a replacement is obtained.
In view of the above, it would be desirable to provide a machine and method to service an automotive automatic transmission which machine and method requires a greatly reduced number of hoses, adapters, and fittings in comparison to conventional machines of this type in order to interface with the transmissions of the most commonly encountered automotive vehicles in the contemporary service environment.